V.90

V.90 was standardized by the International Telecommunication Union(ITU) in February 1998 as the international standard for modems with a transmission speed of 56 kbit/s. Previously, there were two competing de facto standards: K56 with K65plus and K56fex from Rockwell, and X.2 from 3COM.

This standard, which can be seen as a compromise between the two mentioned methods, sets a new standard in modem technology. This technology is ideal for all Internet applications, since this high speed makes it possible to load images, sound or video sequences onto the personal computer( PC) in a short time.

In contrast to all other modem standards, V.90 uses a different approach, namely that the modem transmission to the network is purely digital. Only downstreaming, the direction of transmission from the network connection to the user, is supported at the high transmission rate of 56 kbit/s, while upstreaming is supported at a transmission rate of 33.6 kbit/s, corresponding to the V.34 standard.